image: Pictured is Lawrence T. Reiter, Ph.D., associate professor in the UTHSC Department of Neurology, holds joint appointments in both Pediatrics as well as Anatomy and Neurobiology. view more
Credit: University of Tennessee Health Science Center
Memphis, Tenn. (March 26, 2013) – Identifying and understanding the combination of factors that leads to autism is an ongoing scientific challenge. This developmental disorder appears in the first three years of life, and affects the brain's normal development of social and communication skills. Results from a study led by Larry T. Reiter, PhD, at the University of Tennessee Health Science Center (UTHSC) are providing significant insights into the disorder through the study of a specific form of autism caused by a duplication on chromosome 15. This month his work appears in Autism Research, the official journal of the International Society for Autism Research.
Dr. Reiter, who is an associate professor in the UTHSC Department of Neurology, holds joint appointments in both Pediatrics as well as Anatomy and Neurobiology. His study, which began in 2006, is focused on a sub-group of 14 individuals who have a specific chromosome duplication, known as int dup(15) -- short for interstitial duplications of 15q11.2-q13. Recruitment efforts were spearheaded by a parent support group for 15q duplication known as the Duplication 15q Alliance. Participants underwent a series of tests in order to better understand what autism looks like for those with this chromosome 15q duplication versus those with autism of unknown origin.
"This is the largest study of this particular sub-group ever undertaken at a single location with the same set of investigators," Dr. Reiter said. "We found several interesting points in the course of the study. Consistent with other much smaller studies, we found that maternal duplications of int dup(15) were always associated with autism, while paternal duplications did not always result in an autism diagnosis. We identified a signal in the brain that suggests the individuals with 15q duplication may have elevated levels of a neurotransmitter called GABA in both maternal and paternal duplication subjects. In addition, we identified previously unknown sleep problems in maternal and paternal subjects, which are more severe in the paternal int dup(15) individuals."
"Not only does Dr. Reiter's study make a significant contribution to what is known about how certain genetic abnormalities directly affect brain function, in this case in a subset of patients with autism, but his approach is a great example of how basic scientists can work with clinicians to translate findings from the research laboratory to actual patients to gain important insight into mechanisms of human disease," said Dennis Black, MD, director of the Children's Foundation Research Institute at Le Bonheur Children's Hospital. "We hope that this will set the pace for more translational collaboration in the future across the UTHSC campus and with other institutions," said Dr. Black, who is also the Vice President for Research at Le Bonheur.
On the basic science side, Nora Urraca, MD, PhD, a UTHSC postdoctoral researcher, worked with Dr. Reiter. Their clinical team members at Le Bonheur were Kathryn McVicar, MD, a pediatric neurologist at Le Bonheur, who is also an assistant professor of Pediatrics at UTHSC, and Eniko Pivnick, MD, a pediatric geneticist at Le Bonheur, who also serves as a professor of Pediatrics in the UTHSC Department of Ophthalmology. The project was funded entirely by a grant to Dr. Reiter from the Le Bonheur Shainberg Neuroscience Fund.
Dr. Reiter serves on the scientific advisory board for the Duplication 15q Alliance and Idic15 Canada, two non-profit organizations that provide collaboration, advocacy, and research to families living with both idic and int dup(15), otherwise known as Chromosome 15q11-q13 Duplication Syndrome. He is also a member of both the International Society for Autism Research and the American Society for Human Genetics.
As Tennessee's only public, statewide academic health system, the mission of the University of Tennessee Health Science Center (UTHSC) is to bring the benefits of the health sciences to the achievement and maintenance of human health, with a focus on the citizens of Tennessee and the region, by pursuing an integrated program of education, research, clinical care, and public service. Offering a broad range of postgraduate and selected baccalaureate training opportunities, the main UTHSC campus is located in Memphis and includes six colleges: Allied Health Sciences, Dentistry, Graduate Health Sciences, Medicine, Nursing and Pharmacy. UTHSC also educates and trains cohorts of medicine, pharmacy and/or allied health students -- in addition to medical residents and fellows -- at its major sites in Knoxville, Chattanooga and Nashville. Founded in 1911, during its more than 100 years, UT Health Science Center has educated and trained more than 53,000 health care professionals in academic settings and health care facilities across the state. For more information, visit http://www.uthsc.edu.
Le Bonheur Children's Hospital in Memphis, Tenn., treats more than 250,000 children each year in a 255-bed hospital that features state-of-the-art technology and family-friendly resources. Nationally recognized, Le Bonheur is ranked by U.S. News & World Report as a Best Children's Hospital. Serving as a primary teaching affiliate for the University Tennessee Health Science Center, the hospital trains more pediatricians than any other hospital in the state. For more information, please call (901) 287-6030 or visit lebonheur.org. Follow us on Twitter at twitter.com/lebonheurchild or like us on Facebook at facebook.com/lebonheurchildrens.
Journal
Autism Research